A Tiny Engine That Could

Cell phones and other portable devices are ideal for on-the-go and emergency situationsunless the battery's dead.

Cell phones and other portable devices are ideal for on-the-go and emergency situationsunless the battery's dead. In the growing field of battery alternatives, including fuel cells and solar cells, a tiny, longer-lasting solution is on its way. Engineers at MIT and the Georgia Institute of Technology are developing a microengine that is essentially a fuel tank. About the size of two dimes, it could potentially deliver enough juice to power a notebook.

"With the device we have now we've generated 1.1 watts," says David Arnold, a head researcher at Georgia Tech. "You need more like 20 watts for a laptop, but 50 or 100 watts would be even better. It's feasible."

The microengine will work by using a microturbine to power the microgenerator. The microturbine spins a magnet above a bunch of coils, converting the microturbine's mechanical energy into electrical energy. For anyone who stresses over the dead cell-phone scenario, the researchers are brainstorming a fix for that too, and it's not as high-tech as it sounds.

"It would involve compressed air that you could blow through some blades to turn the magnet," Arnold says. "You could turn a crank in emergency situations."